Thinking about the satirical cartoon that gave us the Gerry-Mander I just naturally assumed that there must be an etymological connection between the words cartoon and lampoon. In common usage they are closely related. We speak of a character being "cartoonish" in the sense of being a comical stereotype. And lampooning is the process of making fun of something, often by invoking just such sterotypes.
But it looks as if the two words are entirely unrelated.
Cartoon derives from the Italian "cartone", that being a sturdy type of paper board suitable for drawing on. Or for making cartons out of. Artwork done on it became "cartoons".
Lampoon is from French and is of "unknown origins". It seems to have come to us from the word "lampons" which means "let us drink", and appears to have been the refrain to a bawdy song of a bygone era. Pushing things still further back lampons comes from "lamper" which means "to drink", and ultimately from a Germanic word "lap" of the same meaning. Lap has of course kept its original intent, but unless very deeply in ones cups lapping up drink is more common among dogs than among their masters.